by Graeme Wood

The world's wheat is defenseless against a new fungus that causes stem rot.  Brendan Koerner says a billion people could die:

The pathogen has already been detected in Iran and may now be headed for South Asia’s most important breadbasket, the Punjab, which nourishes hundreds of millions of Indians and Pakistanis. What’s more, Ug99 could easily make the transoceanic leap to the United States. All it would take is for a single spore, barely bigger than a red blood cell, to latch onto the shirt of an oblivious traveler. The toll from that would be ruinous; the US Department of Agriculture estimates that more than 40 million acres of wheat would be at serious risk if Ug99 came to these shores, where the grain is the third most valuable crop, trailing only corn and soybeans. The economic loss might easily exceed $10 billion; a simple loaf of bread could become a luxury.

The fungus, called Ug99 (sounds a bit like Ice 9, and acts a bit like it too), is a new strain of the same stuff that the late Norman Borlaug won the Nobel for defeating, and thereby possibly saving more lives than anyone has ever lived.

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